Your shopping cart is empty!
K9 Crystal Guides & Knowledge Base
Welcome to the K9 crystal knowledge base from KaiNai Crystal — the factory behind k9crystal.com. Everything about optical K9 crystal in one place: what it is, how it's made, how it compares with glass and natural crystal, full size specifications and engraving guidance. Every guide is written from real factory experience — free to read, print and share. When you are ready to move from reading to ordering, browse the full range of crystal blanks behind every guide below.
. Read all articles on our blog →K9 Crystal Basics
What K9 crystal actually is — and what it isn't. Start here if you're new to the material.
Published
What is K9 Crystal? Composition & Properties
What K9 actually is — an optical BK7-class glass with refractive index 1.5168 and over 92% light transmission — its exact composition, and why the engraving industry adopted it worldwide.
Read the guide →
Published
Crystal vs Glass vs Swarovski
Composition, lead content, refractive index and price compared — which material fits which product line, and why K9 wins at the engraving bench.
Read the comparison →
Published
K9 vs Natural (Real) Crystal
Is K9 "fake" crystal? The structural difference with natural quartz and amethyst — plus four field tests to tell them apart.
Read the comparison →
Published
K9 vs Jade Glass vs White Glass
Three "crystal" materials that look alike in a catalog but behave differently once you customize them — cutting, polishing, engraving and paint-fill differences.
Read the comparison →
Published
What Are Crystal Blanks?
The basic element behind every award, trophy and etched gift: what a blank is, which shapes and sizes are standard, and how buyers specify them.
Read the article →
Published
K9 vs K5 vs K12: Crystal Grades Explained
What the K-series grade numbers actually mean, where each grade is used, and how suppliers misuse them on quotes.
Read the guide →Manufacturing & Quality
From raw batch to polished blank — and insider knowledge that tells good glass from bad.
Published
6 Criteria for Selecting K9 Blanks
How to pick qualified K9 crystal blanks for laser engraving — the six selection criteria that separate award-grade glass from glass that cracks in your customer's hands.
Read the guide →
Published
Why Glass Trophies Outsell Crystal Trophies
An analysis of what buyers actually choose when they stand in front of a trophy catalog — budget, perceived value and where crystal still wins.
Read the analysis →K9 Crystal Weight Calculator
One calculator for every shape we cut: pick the shape, enter the dimensions, get an instant weight estimate in grams and ounces.
Volume = Length × Width × Height ÷ 1000 (cm³)
Weight (g) = Volume × density
Weight (g) = Volume × density
For box, cube and rectangular plaque blanks. Faceted or heavily beveled shapes weigh 15–30% less than the same bounding box.
Estimated weight
759 g
≈ 26.8 oz
Need a custom size, or a shape that isn't listed? We reply within 24 hours —
Request a quote →
